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What a cookie does can only be worked out by looking at the code that uses it. Some of this is only on the server so can't be worked out by viewing the source of a webpage. You'll have to ask the people who wrote the code that created the cookies.
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paulmorrissApr 30 '12 at 15:55

2 Answers
2

The only thing that's ever worked for me, even then usually resulting in limited information, is to just search for the cookies' names. If it's anything interesting, there's generally a discussion someplace where people have already picked it apart as much as possible(ex. 1, ex. 2). But the reality is that in many cases, the companies responsible may not particularly want you to know what they do, so the names will be arcane, sometimes change, and the actual data in the cookies encoded.

Collusion shows who is tracking you, but as far as I'm aware doesn't tell you which cookies are actually involved or what they do. If you know different, please update with a reference link.
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Su'May 1 '12 at 7:57